Understand slice, splice, split, substring thoroughly

Summary of many times, or will be confused, summary more use

slice

The slice() method returns a new array object that is a shallow copy of the array determined by begin and end (not including end). The original array will not be changed. var fruits = ['orange'.'apple'.'banana'.'watermalon'.'durian'];

console.log(fruits.slice(2));
// expected output: Array ["banana"."watermalon"."durian"]

console.log(fruits.slice(2, 4));
// expected output: Array ["banana"."watermalon"]

console.log(fruits);
// expected output: Array ["orange"."apple"."banana"."watermalon"."durian"]

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The slice() method extracts a portion of a string and returns a new string. var str1 ='the HelloWorld! ';
var str2 = str1.slice(4, -2);

console.log(str2); // OUTPUT: oWorl
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splice

The splice() method modifies an array by deleting or replacing existing elements and returns the modified contents as an array. This method changes the original array. var fruits = ['orange'.'apple'.'banana'.'watermalon'.'durian'];

console.log(fruits.splice(2));
// deleted ["banana"."watermalon"."durian"]
console.log(fruits);
// expected output: Array ["orange"."apple"]
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split

English translation: split; The split() method splits a String into an array of strings using the specified delimiter String to split the String into substrings to determine the location of each split. var fruits ="orange, apple, banana, watermalon, durian";

console.log(fruits.split(","));
// expected output: Array ["orange"."apple"."banana"."watermalon"."durian"]
console.log(fruits);
// expected output: "orange, apple, banana, watermalon, durian"
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substring

String, returns a substring, intercepting the string var fruits ="orange"The console. The log (fruits. The substring (1, 3)) / / expected output:"ra"
console.log(fruits)
// expected output: "orange"
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Conclusion: